Investigating Oil-in-Water Emulsions: A Case Study of 1-Hexanol and 1-Octanol

Abstract

Alcohols like 1-hexanol (C₆H₁₄OH) and 1-octanol (C₈H₁₈OH) possess both a hydrophobic alkyl tail (the hexyl group) and a hydrophilic hydroxyl head, allowing them to interact with both water and oil phases. This dual affinity helps reduce the interfacial tension between oil and water, promoting the formation of stable nanoemulsions of hexadecane in water, as confirmed by zeta potential measurements. The effects of non-ionic surfactants, 1-hexanol and 1-octanol on oil nanodroplets are examined through concentration-dependent fluorescence measurements using Nile Red. This fluorescence spectrum also provides valuable information for estimating the critical micelle concentration (CMC), which is crucial for understanding surfactant behavior, as well as the stability and performance of nanoemulsions. Optimizing oil nanoemulsions containing alcohols is essential for various applications, including drug delivery, emulsification, enhanced oil recovery (EOR), food processing, cosmetics and energy storage technologies.

Keywords

• surfactant adsorption
• oil-water interface
• oil nanodroplet
• nanoemulsion
• critical micelle concentration

Ethical Statement

The study is complied with research and publication ethics.

Thanks

The author would like to especially thank Asst. Prof. Halil I. Okur for fruitful discussions and for supporting to access the experimental setup.

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